Hi there...
I would like to recommend the following link that may be helpful in
converting from either from frequency or wavelenght into RGB.
http://plum.ia.polsl.gliwice.pl/~DIP/delphi/Library/Color.htm
In there take a look at :
Color
www.swin.edu.au/astronomy/pbourke/colour
Spectra -- wavelength to RGB, Chromaticity Diagram, Blackbody Radiation
(excellent)
Dan Bruton's Color Science page, www.physics.sfasu.edu/astro/color.html
Hope that this is useful
Sincerely,
Rudy Cazabon
Discreet - a division of Autodesk, Inc.